Microphase separation can occur on a polymersome membrane surface. The phase behavior is dependent on the mixture of charged and uncharged diblock copolymers, as well as the salt concentration in solution [1]. Using molecular dynamics simulations, we evaluate the elastic properties of mixed charged and uncharged diblock copolymer membranes as a function of charged polymer concentration, for the case of divalent counterions in solution. We find that both the area elastic modulus and bending modulus increase as a function of charged copolymer concentration. We find that the membrane thickness decreases and the membrane overlap increases as a function of charged copolymer concentration. We next perform large-scale simulations of a nearly 30 nm polymersome and characterize the growth of domains over 0.5 µs simulation time. We calculate the potential of mean force to form domains using the self-coordination number of the polymers. We characterize the size, shape, and surface topology of the domains as they grow. These results add insight into the underlying mechanisms guiding the growth of domains in both synthetic and living cells.

Domain formation in charged polymer vesicles

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.